Today, projection displays are used more and more to display information on flat panel display screens. Numerous times, for a number of reasons, these screens need also to display simultaneous and synchronized information with the image displayed. For example, if the screen is used for advertising, but the image is produced in advance, simultaneously displaying pricing information that could change from time to time with the specific image would be very helpful and advantageous.
Furthermore, if alphanumeric data is embedded in the projected image, and only one translucent screen is used for viewing from both sides, then although the image can be seen from both sides, the alphanumeric data will be viewed as a mirror image on the opposite side.